Square D️ QO Circuit Breakers
A complete range of Combination AFCI, GFCI, dual-function, and high-frequency GFCI circuit breakers
Square D️ QO Circuit BreakersNew HF-rated GFCI breakers: built for modern appliances like HVAC, EV chargers, and pool pumps, with code-compliant performance.
"The HF-rated GFCI breaker was developed and validated through extensive lab and field testing, backed by over 100 years of Square D expertise." — Poonam Narang, Schneider Electric.
Key benefits of QO circuit breakers
Move to the next job faster
Breakers that trip when they should.
Equipped for modern loads
HF GFCI is built for HVACs, EV chargers and pool pumps.
Less wire clutter
Plug-on neutral (PoN) creates a more organized panel.
Efficient troubleshooting
LED indicators identify issues at a glance.
Streamlined installation
Ready-to-wire lugs help reduce labor time.
Ready for compliance
AFCI and GFCI options help meet NEC requirements in the home.
Connections your way
Choice of plug-on neutral or pigtail connections.
Combination AFCI breaker (CAFCI)
Detects parallel and series arcing in branch circuit wiring before ignition, meeting UL 1699 and NEC 210.12 requirements.
GFCI breaker (Class A)
Trips at 4–6 mA to protect against shock on standard branch circuits. Required by NEC 210.8 in bathrooms, kitchens, garages, and more.
Dual-function breaker (DF)
Combines AFCI and GFCI protection in one device. Use where both 210.8 and 210.12 apply, like kitchens and laundry rooms.
HF-rated GFCI breaker (HF GFCI)
Designed to detect high-frequency leakage from modern loads. Use for HVAC, EV chargers, and pool pumps to improve compatibility.Product features
Product features
Combination AFCI | Dual function | HF-Rated GFCI | |
| Action | |||
Arc Fault (parallel + series) | Combination AFCI and GFCI | High-Frequency Ground Fault | |
| Protection features | |||
| Pole configuration and amperage | 1P / 2P , 15-30 A | 1P / 2P , 15-20 A | 2P , 15-60 A |
| Plug-on neutral (PoN) compatible | |||
| Series arc fault detection | -- | ||
| Parallel arc fault detection | -- | ||
| Ground fault protection - personnel (5mA) | -- | ||
| Advanced features | |||
| High-frequency ground fault detection | -- | -- | |
| Self-diagnostic / end-of-life indication | |||
| Trip cause indication (diagnostic LED) | |||
Square D QO and Homeline HF-rated 2P GFCI circuit breakers
Learn how the Square D QO and Homeline HF-rated GFCI circuit breakers support modern electrical loads, including EV chargers, pool pumps and HVAC systems.
Faster, simpler panel installation
Reduce wiring complexity with QO plug-on neutral load centers for faster, cleaner installs.
Basics of circuit protection for homeowners
A complete guide: Square D advanced circuit protection and how it helps keep homes safe.
General and selection
How do I know if my panel uses QO breakers?
QO™ breakers include the Visi-Trip indicator; a small colored window on the face of the breaker that changes when the breaker has tripped. QO breakers are used in Square D™ QO load centers, which include a model number beginning with "QO" on the panel label. QO and Homeline™ are not interchangeable. Each breaker type fits only its corresponding load center.
What's the difference between QO and Homeline breakers?
QO and Homeline are both Square D residential circuit breakers, but they fit different load centers and cannot be substituted for each other. QO breakers have ¾-inch per pole size, while Homeline circuit breakers have 1-inch per pole size. QO breakers also feature a visible trip indicator (Visi-Trip) window and are generally considered the premium line for residential, light commercial, and three-phase work in QO load centers. Homeline circuit breakers are used in Homeline load centers and offer broad residential coverage at a value price point. Both families include standard Ground Fault Circuit Interrupters (GFCI), Combination Arc Fault Interrupters (AFCI), Dual Function, and High-Frequency (HF)-rated GFCI options.
What amperages are available in the QO breaker family?
QO 1-pole standard circuit breakers are available from 15-70 A, and 2-pole standard circuit breakers are available from 15-200 A. QO 1-pole Arc Fault or Dual Function circuit breakers are available in 15 and 20 A. QO 1-pole GFCI circuit breakers are available from 15-30 A, while 2-pole GFCI circuit breakers are available from 15-60 A.
HF-Rated GFCI
What is an HF-rated GFCI and when should I use one?
An HF-rated GFCI is a Class A GFCI certified under UL 943 HF to maintain personnel protection across leakage current at frequencies above 60 Hz. HF-rated circuit breakers should be specified for circuits serving equipment with variable-speed drives or power-conversion electronics, including heat pumps, mini-splits, EV chargers, pool pumps, and well pumps. HF-rated GFCIs can be used anywhere a standard Class A GFCI is used. They provide the same level of ground fault protection.
What is the NEC 2026 GFCI requirement for HVAC equipment?
Effective September 1, 2026, NEC 210.8(F) requires GFCI protection on outdoor 208V/240V single-phase HVAC equipment in dwelling units, rated 60A or less such as heat pumps, AC condensers, and outdoor units, where adopted. The prior HVAC exception (Exception 2) expires that date. Variable-speed HVAC systems can produce high-frequency leakage from VFDs that nuisance-trips standard Class A GFCIs. NEC 2026 permits two compliance paths: Class A HF-rated GFCI (5 mA, UL 943 HF certified). QO 2-pole HF-rated GFCI circuit breakers are designed for HVAC systems, where high frequency leakage currents commonly cause unwanted tripping.
Why does my GFCI circuit breaker keep tripping. What should I check?
Unwanted GFCI tripping has several possible causes beyond a true ground fault. Check for: moisture in outdoor or damp-location receptacles and conduits, LED lighting drawing inrush current on the same circuit, long cable runs with capacitive coupling, wiring errors such as shared or improperly bonded neutrals, or modern variable-speed equipment producing high-frequency leakage. The fix depends on the cause. Wiring errors and moisture need correction at the source, while high-frequency leakage from variable-speed equipment is typically resolved by specifying an HF-rated GFCI breaker.